wiki:bullets

Bullets are similar to arrows in that they're not an actual weapon, but can be equipped and are necessary to attack with any gun weapons. Unlike arrows, there is only a small variety of bullets, and they come in two types: Bullets and Spheres.

The basic bullets are usable with any gun with the exception of Grenade Launchers and can be purchased or exchanged from NPCs in the gunslinger guild located in Einbroch (einbroch 136, 199). 500 Bullets can be stored in a Bullet Case similar to an Arrow Quiver.

Note : You must be on a gunslinger for the NPC to make Bullet Cases for you.
Second Note : You can give bullets some Elements with the Elemental Bullet Trader
Third Note (Loki) : Bullets, along with Elemental bullet cases can be purchased from the NPC in the mall.

Name	atk	Weight	Price	element	Effect

Bullet

10

0.2

1

neutral

-

Silver Bullet

15

0.2

15

holy

-

Bloody Shell

30

0.2

30

neutral

bleeding by chance

Spheres are a special type of bullet that may only be fired with Grenade Launchers. They must be crafted by an NPC at the gunslinger guild, rather then bought, and come in five different elements. Spheres may also be put into Bullet Cases.